Thread: file index update error

I'm doing a project on data management using indexes. I am able to initially create,

read, & write Index. but when updating Index after a data record addition or deletion, I

encounter problems. When the Index is written back to file for update, it is written

incorrectly. I've narrowed down the problem to these code, I think.

Additions:

Code:

//new record goes under location found by binary srch
//shift index for additional entry
//addkey is global var
void indexinsert(const int& location, Index dindex[], int& size, const int& trrn){
	int i;
	dindex = (Index*) realloc (dindex, (size+1) * sizeof(Index));
	if (dindex==NULL) exit (1);


	for(i = size; i > location; i--){
		dindex[i] = dindex[i-1];
	}

	strcpy(dindex[location].key,addkey);	
	dindex[location].rrn = trrn;

	size++;
	return;
}

below is the "tail" of the Index file. the new index entry is placed at end & is junk,

not what I intended. can't figure what went wrong.

N583FE|12
N711AV|23
N8500R|15
N87BC |1
N97890|25
TC-THG|13
|538976288

Deletions:

Code:

//data record of index entry @ location deleted
//shift index for update
void indexdelete(const int& location, Index dindex[], int& size){
	int i;
	for(i = location; i < (size-1); i++)
		dindex[i] = dindex[i+1];
	size--;
	return;
}

deletion of 1 data record ok, but a second record deletion results in this index below.

index is updated properly, but there is extra junk at end of file (last line). I think

it is written to file by my code rather than left over by the file, as I've closed the

index file from reading & reopened it for writing with fopen mode "wb" to clear out

previous file contents.

N51126|24
N5638J|10
N583FE|12
N711AV|23
N8500R|15
N87BC |1
N97890|25
TC-THG|13
|0

for more reference, here's the index file output code:

Code:

void finalindex(Index data[], const int& size, FILE* dfile){

	//write each entry of sorted index to file.
	int i;
	for(i = 0; i < size; i++){
		fputs(data[i].key,dfile);
		fputs("|",dfile);
		fprintf(dfile,"%d",data[i].rrn);
		fputc(10,dfile);
	}
	return;
}

Or is problem elsewhere?